Blind tadpoles were able to process visual data from eyes grafted onto their tales after being treated with a "neurotransmitter drug" that improved the organs' integration and function.

The study was conducted by scientists at the Allen Discovery Center of Massachusetts-based Tufts University and published in Regenerative Medicine on Thursday.

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The results show promise for the future of regenerative health, an area of study often hampered by lack of progress in the field of innervation, the absence of a supply of nerves to a body part.

After grafting eyes onto the tails of blind tadpoles, scientists treated them with Zolmitriptan, a substance currently used to treat migraine headaches. Zolmitriptan is a "serotonin receptor agonist," a compound that activates serotonin receptors 1B and 1D, which are associated with neural development.

Tadpoles exposed to the drug displayed an increase in "graft innervation" that didn't alter or damage their nervous systems.

Scientists then tested the subjects' abilities to differentiate between colors using a test that encouraged them to occupy a blue space instead of a red space. Seventy-six percent of sighted tadpoles passed the test, while only three percent of blind tadpoles were able to tell the difference.

Only 11 percent of blind tadpoles with eye grafts passed the test, but 29 percent of tadpoles treated with Zolmitriptan were able to distinguish between the two colors.

Additionally, fifty-seven percent of tadpoles with eye grafts treated with the serotonin compound were able to follow a series of rotating images, while only 38 percent of blind tadpoles and 32 percent of tadpoles with untreated eye grafts were able to do so.

"For regenerative medicine to move forward and enable the repair of damaged tissues and organ systems, we need to understand how to promote innervation and integration of transplanted organs," said Michael Levin, Ph.D., Director of the Allen Discovery Center at Tufts.